1. Field of the Invention
The present invention relates to fire containment systems; and, more particularly, to a lightweight portable fire resistant containment system for preserving memory objects such as photographs, documents and the like in case of a fire event.
2. Description of the Prior Art
Many patents address issues related to fireproof containment boxes. The patents and patent publications that disclose fireproof containment are discussed below.
U.S. Pat. No. 2,613,623 to Preston et al. discloses an insulated filing cabinet construction. The file cabinet is made from steel casing that forms a plurality of rectangular boxes. Each wall of the casing contains insulating material. Inherently, the insulated filing cabinet disclosed by the '623 patent is a heavy weight device, as shown by the requirement of casting wheels at the bottom. The insulating material is not indicated to withstand high temperature exposure.
U.S. Pat. No. 3,408,966 to Gartner discloses a fireproof container. This fireproof container has an inner container surrounded by an outer container. A heat protection liner made from fibrous material having high temperature insulation properties is provided between the outer frame and the inner container. A jamb having an irregular undersurface portion with fibrous material is positioned in mating relationship with the jamb, providing a torturous heat flow closure path. The fireproof container has an outer shell of cold rolled steel, an inner container of molded plastic, and two layers of fibrous high temperature resistant fibers, followed by heat insulative fibers. Such a fireproof container, as disclosed by the '966 patent, is a heavy object. It is not made entirely from lightweight high temperature resisting fibers that have a high level of porosity, providing insulation properties.
U.S. Pat. No. 3,855,741 to Semon discloses a closure for a fire resistant structure. This container is protective against a high temperature of restricted duration. The cast container with plaster of Paris is destroyed by high temperature exposure, while the magnesium sulfate hydrate degrades in steps, leaving behind a fire resistant composition. This fire resistant structure has a facing of low melting glass cloth with epoxy bond. Such a fire resistant structure is not made from fibrous material.
U.S. Pat. No. 4,048,926 to Brush, Jr. et al. discloses a safe. The safe has a non-metallic outer shell, an inner shell with molded insulation material therebetween. The molded material is indicated to have a substantial amount of chemically bonded water similar to foamed Portland cement. The safe is not made from ceramic fibrous material.
U.S. Pat. No. 4,263,365 to Burgess et al. discloses a fire-resistant safe and panel. This safe has a heat absorbing body made from a mixture of water, Portland cement, cellulose fibers, and a foaming agent, with or without other ingredients such as water glass and sodium sulfate. Polypropylene fibers may be used in place of part or all of the cellulose fibers. The safe has a plastic outer shell and an inner shell made from plastic or steel. The space between the inner and outer shell is filled with foamed cement composition that has recycled cellulose fibers. Sodium silicate may be added to the cement mixture. The composition resists fire by breaking down water of hydration as it crumbles by heat. Cement is heavy and consequently the safe is not portable. The safe does not use fire resistant ceramic fibers.
U.S. Pat. No. 4,272,137 to Rothhaas discloses a fire resistant cabinet with a protective void in a gypsum filling. A heat resistant cabinet has a gypsum filling provided in the interspace between the outer casing and the inner surface. This filing cabinet has a metal sheet outer surface with a gypsum filling. The gypsum filling has a hollow space provided for subsequent use as an air gap space or filling by plastic foam. Gypsum decomposes when exposed to heat by loss of water of hydration, essentially crumbling the gypsum layer. The gypsum sheet is indicated to crack especially around the free space area. This is a heavy cabinet and not a portable device.
U.S. Pat. No. 4,307,543 to Schulthess discloses a door. This door is primarily intended for applications that require a fire resistant door. The door has a metal frame with a foamable strip present in the rebate of the door. The strip foams when heated by a fire, sealing the door. The '543 disclosure does not provide a flameproof portable box for containment of photographs and documents.
U.S. Pat. No. 4,721,227 to Hughes et al. discloses a fire-resistant container. This fire-resistant container is said to protect magnetic media such as floppy discs, and comprises a base and a cover. The fire resistant metal container is filled with compressed insulation designed to expand when the outer layer is expanded by application of heat. Inside the insulation is a container filled with molten and solidified wax that will melt at 50° C., preventing the contents of the fire-resisting container beyond 50° C. An aluminum foil cover is provided on either side of the wax container to equalize hot spots. The fire-resistant container disclosed by the '227 patent is not a lightweight fire resistant box; it is not made from fireproof ceramic fibers. Instead, the insulation of the '227 container is composed of silica powder with some silica or alumina fibers for reinforcement.
U.S. Pat. No. 4,735,155 to Johnson discloses a fire resistant enclosure. The casing and door for this enclosure is made from resinous material such as epoxy polyimide or polyvinyl chloride that chars readily. The resin may be reinforced with mineral fiber in the form of glass wool, and protected with heat reflecting aluminum sheet. The enclosure is a multi-component heavy device. It does not rely on the fire resistance of a ceramic fiber and does not rely on the porosity of the ceramic fiber matrix to resist heat flow.
U.S. Pat. No. 4,741,276 to Pollock discloses a fire resistant cabinet. This is a heavy fire resistant cabinet made from an inner casing of steel and an outer container of steel. The space between these casings is filled with hydrated sodium metasilicate, a phase change material. The space between the inner and outer casing has a plurality of metal foils parallel to the outer casing in order to reflect heat. The fire resistant cabinet disclosed by the '276 patent is not a lightweight fire resistant containment system, and it does not use fire resistant ceramic fibers.
U.S. Pat. No. 5,152,231 to Preston et al. discloses a fire-resistant safe. This fire resistant safe is made from resin sheets that form the interior enclosure and exterior enclosure with insulation provided there between. As the resin catches fire, it produces vertical channels for the passage of air, promoting vigorous combustion. Vertical air flow is prevented (i) by use of corner jambs that are made thin, thereby producing a narrow air flow, restricted pathway, or (ii) by use of compressively loaded resin sheets. The fire resistant safe disclosed by the '231 patent does not use ceramic fibers.
U.S. Pat. No. 5,970,889 to Shaffer et al. discloses a steel shell safe with a snap-in resin liner. This safe has an outer steel shell with a resin liner inserted there within. An insulation material is provided between the steel shell and the resin liner. The steel shell safe with snap in liner is heavy and is not a portable light weight product. It does not use fire resistant ceramic fibers.
U.S. Pat. No. 6,170,481 to Lyons et al. discloses an open-ended molded fireplace box and method. This is a molded ceramic fiber insert that is directly cast into a heavy steel component which is designed to be inserted into a fireplace. This fireplace insert is not a portable lightweight box that uses porously bonded fire resistant ceramic fibers; it is not designed to protect photographs and documents.
U.S. Pat. No. 6,752,092 to Beattie et al. discloses a fire and water-resistant container. The bottom and top shells are made from metal or resin and the space there between is filled with a fire proof insulator, which is hydrated Portland cement. The container is therefore heavy due to the cement insulation. The hydrated Portland cement will disintegrate due to loss of water of hydration when exposed to fire. The shell, hinge and gasket may also be destroyed by fire as indicated in the '092 patent. The fire and water-resistant container does not use fire resistant ceramic fibers.
Foreign Patent Application No. JP 08270323 to Hineno discloses a fireproof safe. A box has an outer case that contains an inner case. The space between the two cases is filled with burnt ash of activated carbon, which is a very porous carbon material. The burnt activated carbon ash is no longer a fiber and therefore, it is not a fire resistant ceramic fiber. The type of material used for the outer case and the inner case is not indicated.
There remains a need in the art for a lightweight portable fire resistant containment system that saves valuable photographs and documents in an unaffected condition even when exposed to a fire lasting for up to 30 minutes.